<template>
  <div>
      学生年龄总和:{{num}}
  </div>
</template>

<script>
export default {
  data () {
    return {
      arr: [{
        name: '小明',
        age: 18
      }, {
        name: '小花',
        age: 25
      }, {
        name: '小爱',
        age: 21
      }],
      num: 0
    }
  },
  created () {
    this.arr.forEach((item, index) => {
      this.num += item.age
    })
  }

}
</script>

<style>

</style>
